DE102005004080A1 - Electromagnetic pressure control valve arrangement for hydraulic clutch, has electronic part with pressure sensor measuring hydraulic pressure applied to load connection, where sensor is placed on magnetic part end, which faces valve part - Google Patents

Abstract

The arrangement has a magnetic part with a coil body supporting an electrical coil. A valve part has inlet, return and load connections and a control unit that cooperates with a valve seat and is actuated by an anchor. An electronic part has a pressure sensor (70) measuring hydraulic pressure applied to the load connection. The sensor is arranged on an end of the magnetic part, where the end faces the valve part on the electronic part.

Description

The The invention relates to an electromagnetic pressure control valve device for controlling a hydraulic pressure including a pressure regulating valve with a magnetic part, the at least one an electrical coil carrying bobbin, a coil core and a slidably guided anchor, with a Valve part, the at least one inlet connection, a return connection, a consumer connection and an armature operated and with a valve seat cooperating valve closure member has, and with an electronic part, the at least one pressure sensor for measuring the hydraulic pressure present at the consumer connection according to the preamble of claim 1.

to Control of clutches in stepped automatic transmissions are pilot valves with downstream hydraulic amplifier or actuators for Variation of clutch pressures applied. In this case, the pilot pressure is a forward-facing Impact chain, so controlled, set. This principle has two decisive disadvantages: Neither the time variance of the route, due to changes ambient conditions (e.g., temperature), any disturbances (e.g., change the inlet pressure) can be sufficiently compensated. Thus, both the stationary and the dynamic behavior unsatisfactory. These disadvantages will be largely eliminated by a closed loop, wherein an integral part of the control loop is a control variable measuring Sensor member, forms a pressure sensor in the present case.

It is advantageous to integrate the pressure sensor in the electrohydraulic actuator of the control loop, ie in the pressure control valve, as this reduces the assembly costs for the customer. Such a solution is for example in the generic EP 0 971 278 A1 described. There, the pressure to be controlled is measured by a pressure sensor arranged in the magnetic part and more precisely in an armature housing of the pressure regulating valve. For this purpose, the pressure signal present in the valve part must be passed through the armature housing. The pressure connection guided through the armature housing corresponds in the hydraulic sense to a long line with comparatively high geometric complexity and length and represents a hydraulic transmission path along which the measured variable pressure is filtered. As a result, both amplitude and phase of the signal change, which is disadvantageous in that pressure signals can only be faithfully transmitted to a relatively low cutoff frequency. As a result, there may be an undesirable falsification of the measurement result.

Advantages of invention

The Invention is based on the idea of measuring the hydraulic pressure preferably to measure near the valve part, since there generates the pressure change becomes. Therefore, the pressure sensor at a valve part facing End of the magnetic part arranged. Due to the valve part near the arrangement of Pressure sensor, the filter effect of the transmission line is clear reduced and the hydraulic pressure to be measured can be up to a significant higher corner frequency transmitted without errors become. this leads to a higher one Measuring and consequently also to a higher control accuracy of Pressure control valve.

A direct arrangement of the pressure sensor on or in the valve part itself fails in practice because pressure control valves often with its valve member inserted into a receiving bore of a valve block be and only the Mag netteil protruding from the mounting hole. Then the pressure sensor connected to electrical cables can turn off space limitations not be placed directly on the valve part.

By in the subclaims listed activities are advantageous developments and improvements in the independent claim specified invention possible.

In the electromagnetic pressure control valve according to the EP 0 971 278 A1 the pressure sensor must be in communication with the remote control unit via five electrical leads, one for the pressure sensor signal, one for the pressure sensor, one for the pressure sensor, another for the coil and the ground for the coil another line is used to power the coil. However, there is a risk that the sensor signal is corrupted due to electromagnetic interference.

According to a particularly preferable embodiment of the invention, not only the pressure sensor, but also the signal and power electronics for operating the electromagnetic pressure control valve is integrated into its electronic part. In this case, the transmission of low-power sensor signals takes place over very short distances within the electronics housing and the EMC sensitivity is reduced. For example, the electronic part integrated in the pressure regulating valve contains, in addition to the pressure sensor at least one of the following: A power supply for the pressure sensor, a communication interface to a higher-level electronic control unit, a microprocessor or an analog control electronics, which calculates the control variable from a control deviation between a pressure actual value and a pressure setpoint, a power electronics for power supply Coil, capacitors for signal filtering and EMC (Electromagnetic Compatibility) fuses and a diagnostic device. The superordinate electronic control unit can be designed to control a plurality of pressure control valves, but the control deviations of the various pressure control valves should preferably be calculated in the electronic part of the respective pressure control valve itself.

• – Es ist robust gegenüber elektromagnetischer Beeinflussung,
• – es kann ohne wesentliche Einbußen so befiltert werden, dass es selbst wenig Störspannung aussendet (geringe Phasendrehung, für die Übertragung der Führungsgroße tolerierbar),
• – es kann in der Stromstärke so eingestellt werden, dass die Selbstreinigung von elektrischen Kontakten ausreichend gut ist und die Verlustleistung dennoch nicht zu groß wird.

Due to the smaller distances for the electrical transmission of the sensor signals can be dispensed with a costly shielding. When integrating the control and power electronics in the pressure control valve this can be realized with only three leads. The supply voltage is transmitted via a line, the command variable (pressure) and diagnostics / status information are transmitted via another bidirectional line, and a third line forms the connection to ground. This reduces the number of connecting lines between the central control unit and the pressure control valve from five to three lines. In particular, it is advantageous that small current-carrying lines are omitted and thus eliminates the known problem of then low self-cleaning of contacts in polluted environment. The single signal line then transfers, for example, both the reference variable and the diagnostic / status signal with bidirectional protocol. To improve the electromagnetic robustness, for example, a pulse width modulated signal is used. The transmission can be digital and with time control. This protocol has the following advantages:

• - It is robust against electromagnetic interference,
• It can be filtered without significant losses so that it itself emits little interference voltage (low phase rotation, tolerable for the transmission of the guide variable),
• - It can be adjusted in the amperage so that the self-cleaning of electrical contacts is sufficiently good and the power loss is still not too large.

Prefers the electronic part is in the area of a valve part facing End of the coil and if the pressure control valve with its valve part is inserted into a receiving bore of a valve block, especially preferably in the region of a parting plane between the valve part and arranged from the receiving bore outstanding magnetic part, more precisely between the valve part facing the end of the coil and the parting plane.

According to one the first variant, the electronics part directly to a the Coil-carrying bobbin be flanged. According to one second variant, the electronics part directly to a the filter port associated with the consumer port and the valve member at least partially enclosing filter support be flanged.

In both cases Must have a short hydraulic connection between the pressure sensor and the consumer port or with a formed in the valve part, with the consumer connection associated pressure chamber are provided, which then in the first variant in the bobbin and according to the second Variant in the filter carrier is trained.

Of the Structure of the device according to the invention is best understood from the following description of embodiments clear.

drawing

In the drawing shows

1 a cross-sectional view of an electromagnetic pressure control valve according to a preferred embodiment of the invention;

2 a cross-sectional view of an electromagnetic pressure control valve according to another embodiment of the invention.

Description of the embodiments

This in 1 shown preferred embodiment of an electromagnetic pressure control valve 1 a pressure control valve device according to the invention is used for example for controlling the hydraulic control pressure of a hydraulic clutch in a stepped automatic transmission of a motor vehicle. The pressure control valve 1 includes, among other things, a magnet part 2 and a valve part 4 ,

The magnetic part 2 is from a magnet sleeve 6 enclosed and includes one on a bobbin 8th wound coil 10 , one inside the coil 10 protruding bobbin 12 and one in the coil core 12 axially movably guided anchor 14 , For this purpose, the bobbin core 12 a stepped core hole 16 on, in its larger diameter section 18 the anchor 14 is guided while in a valve part side subsequent bore section 20 smaller diameter, a control piston 22 is mounted longitudinally movable, the one end side an end face of the armature 14 contacted. With a center hole 24 on its other end is the anchor 14 by a return spring 26 against one on the valve part 4 opposite end of the spool core 12 patch cap 28 supported. Between the one end of the anchor 14 and the bottom of the larger diameter bore section 18 the core hole 16 there is a working gap in the axial direction 30 , The bobbin 8th extends in the axial direction substantially from one free end of the magnetic part 2 to the free end of the valve part 4 , being at his the valve part 4 facing the end of a river fork 32 wearing.

The valve part 4 again, for example, has a pressure side of a pressure generator 34 connected inlet connection 36 one with a tank 38 for the hydraulic fluid connected return port 40 , a consumer connection connected to the clutch 42 and one from the anchor 14 operated and with a valve seat 44 cooperating actuator 46 on. The actuator consists for example in one of the actuator piston 22 worn seat pane 46 , which with one in the bobbin 8th trained flat seat 44 to cooperate. The flat seat 44 is at a bore edge of a central through-hole 48 of the bobbin 8th formed, which is the return port 40 with a pressure chamber 50 connects when the seat disc 46 from the flat seat 44 is lifted off. On the other side of the pressure chamber 50 has the bobbin 8th another, designed as a throttle bore through hole 52 on, through which the adjusting piston 22 projecting end and a closing ball 54 can contact, which at the one of the pressure chamber 50 opposite edge of the throttle bore 52 trained valve seat 56 depending on the position of the actuator piston 22 close or release and thus a flow connection between the pressure chamber 50 and the inlet connection 36 at the bottom of the valve part 4 can manufacture or lock. Through the inlet connection 36 in the flow direction upstream screen filter 60 prevents impurities in the hydraulic fluid in the pressure control valve 1 reach.

The sieve filter 60 is from a sleeve-shaped filter carrier 62 carried, which is substantially the entire circumference of the valve member 4 encloses. In particular, the filter carrier forms 62 a peripheral wall of the pressure chamber 50 in which the consumer connection 42 is formed and carries on its radially outer peripheral surface O-rings 64 , via which an outflow of hydraulic fluid to the wall, not shown, of a receiving bore to be prevented, in which the valve member 4 is plugged and from which the magnetic part 2 protrudes. In the valve block further pressure control valves may be included, which from a common, higher-level electronic control unit 66 are controlled.

Furthermore, the pressure regulating valve 1 an electronic part 68 on, the at least one pressure sensor 70 for measuring the at the consumer connection 42 pending hydraulic pressure includes. This is preferably the pressure sensor 70 containing electronic part 68 in the area of the valve part 4 facing end of the coil 10 and in the present case, when the pressure control valve 1 with its valve part 4 is inserted into a receiving bore of a valve block, particularly preferably in the region of a parting plane 72 between the valve part 4 and the protruding from the receiving bore magnetic part 2 arranged, more precisely between the valve part 4 facing the end of the coil 10 and the dividing plane 72 ,

According to a particularly preferable embodiment of the invention, not only the pressure sensor becomes 70 , but also the signal control and power electronics 74 for operation of the electromagnetic pressure control valve 1 in his electronics part 68 integrated. For example, the includes in the pressure control valve 1 integrated electronics part 68 next to the pressure sensor 70 at least one of the following: A power supply for the pressure sensor 70 , a communication interface to the parent electronic control unit 66 , a microprocessor or an analog control electronics, which calculates the manipulated variable from a control deviation between a pressure actual value and a pressure setpoint, power electronics for powering the coil, capacitors for signal filtering and EMC (Electromagnetic Compatibility) hedge and a diagnostic device.

According to a further embodiment, the electronic part 68 only the pressure sensor 70 include and the sensor signal is sent through a single signal line to the parent controller 66 transfer.

The electronics part 68 is for example in a separate electronics housing 78 housed, which on a lateral connection surface 80 of the bobbin 8th is flanged. In the integration of signal control and power electronics 74 in the electronics part 68 of the pressure control valve 1 With just three electrical connection cables, all necessary connections to the higher-level control unit can be made 66 getting produced. About a line 82 the supply voltage is transmitted via another bidirectional line 84 the reference variable (pressure) and diagnosis / status information and a third line 86 makes the connection to the earth.

From the electronics housing 78 protrudes a hydraulic connection pipe 88 of the pressure sensor 70 , which in one in the bobbin 8th trained transverse bore 90 is taken, which in turn via an axial, parallel to a central axis 92 of the pressure control valve 1 extending connection channel 94 in the bobbin 8th with the pressure chamber 50 or with the consumer connection 42 communicates. Since the bobbin 8th is preferably formed by an injection molding of plastic, it offers the possibility, without manufacturing overhead, a hydraulic connection for the built-in electronic part pressure sensor 70 manufacture. In 1 are the wires 82 . 84 . 86 corresponding connection pins of the electronic part 68 shown, which are contacted by an associated connector preferably with an insulation displacement connection or a pressure contact.

A particular difficulty in hydraulic systems is the venting. Non-vented pressure sensor connections can lead to incorrect measurements due to the additional elasticity introduced with the air. A particular advantage of the present solution is that a venting of the pressure sensor 70 can be performed by the hydraulic connection pipe 88 without sealing ring in the transverse bore 90 is introduced. By a suitable design of this transverse bore 90 , For example, by targeted introduction of surface roughness, longitudinal grooves, or out-of-roundness in the radially inner peripheral surface of the transverse bore 90 can via a low leakage forced ventilation of the pressure sensor 70 be achieved. To the pressure sensor 70 between a connection surface 80 of the bobbin 8th and a connector housing 98 To stretch elastically is between a bottom of the electronics housing 78 and the pad 80 for example, an O-ring 96 arranged.

On the other hand defines the end face of the connection pipe 88 of the pressure sensor 70 an area to which the measured, at the consumer terminal 42 Pending hydraulic pressure acts. The resulting pressure force is through a connector housing 98 made of injection-molded plastic, with a molded ring section 100 over the magnet sleeve 6 is pushed and the electronics housing 78 embraces. Thus, the on the pressure sensor 70 acting forces in the pressure control valve 1 self-supported.

Against this background, the operation of the pressure control device is as follows: In the energized state of the coil is the closing ball 54 due to the inlet connection 36 prevailing, on the pressure side of the pressure generator 34 pending hydraulic pressure against the associated valve seat 56 curious; excited. The relatively weak return spring 26 , whose pressure force over the anchor 14 and the actuator piston 22 on the closing ball 54 However, this is not able to transfer from the valve seat 56 withdraw. Thus, the inlet connection 36 opposite the consumer connection 42 and the return port 40 blocked. However, the seat pane is 46 from their associated flat seat 44 lifted off, allowing hydraulic fluid from the clutch via the consumer port 42 to the with the return port 40 connected tank 38 can flow out. There is a control edge 102 the seat pane 46 in a position where it does not have a throttling function, so that at the consumer terminal 42 the pressure of the return connection 40 prevails.

In contrast, the closing ball 54 in the energized state of the coil 10 by the deflection caused by magnetic forces of the armature 14 and the actuator piston 22 put in open position. Then hydraulic fluid flows from the pressure generator 34 in the inlet connection 36 and from there into the throttle hole 52 and divides into a partial flow to the consumer connection 42 and to the return port 40 out. The seat pane 46 has it with her control edge 102 the flat seat 44 approximated, so they from the inlet connection 58 to the return connection 40 flowing partial flow throttles. By the amount of current flow of the coil 10 may be the measure of the anchor 14 and thus the actuator piston 22 issued deflection movement are electrically changed, whereby the throttle ratios of the control edge 102 and the pressure conditions at the consumer connection 42 can be regulated application-specific, for example in such a way that the partial flow to the consumer connection 42 is negligible and essentially only a pressure signal is applied to it, while the partial flow through the return port 40 almost all the current through the inlet connection 58 equivalent.

This in 2 shown second embodiment of a pressure control valve 1 differs by a modified structure. Modified components of the second embodiment are characterized below by the index a, while for identical components, the position numbers of 1 were taken over.

One of the differences is that the electronics part 68 directly on the filter carrier 62a flanged, which is at least one side over the parting line 72 out to substantially the level of the valve member end of the coil 10 extends. Furthermore, it opens parallel to the central axis 92 of the pressure control valve 1 extending, from that of the transverse bore 90 outgoing connection channel 94a directly into the consumer connection 42a and is like this in the filter carrier 62a educated.

Claims (14)

Electromagnetic pressure regulating valve device for controlling a hydraulic pressure including at least one pressure regulating valve ( 1 ) with a) a magnetic part ( 2 ), which has at least one electrical coil ( 10 ) carrying bobbin ( 8th ), a coil core ( 12 ) and a displaceably guided anchor ( 14 ), b) a valve part ( 4 ), which has at least one inlet connection ( 36 ), a return port ( 40 ), a consumer connection ( 42 ) and one from the anchor ( 14 ) and with a valve seat ( 44 ) co-operating actuator ( 46 ), and with c) an electronic part ( 68 ), the at least one pressure sensor ( 70 ) for measuring the at the consumer connection ( 42 ) has pending hydraulic pressure, characterized in that d) of the electronic part ( 68 ) at least the pressure sensor ( 70 ) on a valve part ( 4 ) facing the end of the magnetic part ( 2 ) is arranged. Pressure control valve device according to claim 1, characterized in that the electronic part ( 68 ) in the region of the valve part ( 4 ) facing the end of the coil ( 10 ) is arranged. Pressure regulating valve device according to claim 1 or 2, characterized in that the pressure regulating valve ( 1 ) with its valve part ( 4 ) is inserted into a receiving bore of a valve block, wherein the electronic part ( 68 ) in the region of a parting plane ( 72 ) between the valve part ( 4 ) and the protruding from the receiving bore magnetic part ( 2 ) is arranged. Pressure control valve device according to claim 2 and 3, characterized in that the electronic part ( 68 ) the valve part ( 4 ) facing the end of the coil ( 10 ) and the parting plane ( 72 ) is interposed. Pressure regulating valve device according to at least one of the preceding claims, characterized in that the electronic part ( 68 ) directly on which the coil ( 10 ) carrying bobbin ( 8th ) is flanged. Pressure control valve device according to at least one of claims 1 to 4, characterized in that the electronic part ( 68 ) directly to a consumer terminal ( 42 ) associated filter ( 60 ) carrying and the valve part ( 4 ) at least partially enclosing filter carrier ( 62a ) is flanged. Pressure control valve device according to at least one of the preceding claims, characterized in that a hydraulic connection ( 94 ; 94a ) between the pressure sensor ( 70 ) and the consumer connection ( 42 ; 42a ) or with one in the valve part ( 4 ), with the consumer connection ( 42 ) communicating pressure chamber ( 70 ) is provided. Pressure regulating valve device according to claim 7 and claim 5, characterized in that the hydraulic connection ( 94 ) in the bobbin ( 8th ) is trained. Pressure regulating valve device according to claim 7 and claim 6, characterized in that the hydraulic connection ( 94a ) in the filter carrier ( 62a ) is trained. Pressure control valve device according to one of claims 8 or 9, characterized in that at from the valve seat ( 44 ) lifted actuator ( 46 ) the pressure chamber ( 50 ) with the return port ( 40 ). Pressure regulating valve device according to at least one of the preceding claims, characterized in that the valve part ( 4 ) in the further a throttle point ( 52 ) between the pressure chamber ( 50 ) and the inlet connection ( 36 ), which with a on the one hand by the inlet pressure and on the other hand by the anchor ( 14 ) loaded closing member ( 54 ) cooperates. Pressure regulating valve device according to at least one of the preceding claims, characterized in that the electronic part ( 68 ) further comprises at least one of the following: A power supply for the pressure sensor ( 70 ), a communication interface to a higher-level electronic control unit ( 66 ), a microprocessor or an analog control electronics, which calculates a control variable from a control deviation between a pressure actual value and a pressure setpoint, a power electronics ( 74 ) to power the coil, capacitors for signal filtering and EMC protection, a diagnostic device. Pressure regulating valve device according to claim 12, characterized in that the pressure regulating valve ( 1 ) via three electrical lines with the electronic control unit ( 66 ): a line ( 82 ) to the power supply, another bidirectional line ( 84 ) for transferring the reference variable (pressure) and diagnosis and / or status information and another line ( 86 ) to connect to earth. Pressure regulating valve device according to at least one of claims 1 to 11, characterized in that the electronic part ( 68 ) only the pressure sensor ( 70 ) and the sensor signal by a sig to a higher-level control unit ( 66 ) is transmitted.